I bought these refills in blue, black, and red for my uniball jetstream
multi-pen. None of the colors perform as expected. I use this pen daily at work,
and have found that after only 25-50% of the cartridges have been used, the ink
loses its color intensity and begins skipping. I am replacing ink much more
frequently than should be necessary. I will continue to use until my stash of
refills is exhausted (since the money has already been spent), then will trash
the pen. Do not recommend, will not repurchase.

I have been buying jetstream refills for several years. But I agree in the last
12-18 months the refills are hit and miss. About 1 in 4 perform the way they
used to. The others leak, "skip" and don't have a nice flow or stop working all
together. I probably have about 8 variations of the jetstream and am hesitant to
have to change all of them to another brand.

Great color! The intensity of the ink is dark and the ink flows well. I have no
reservation about this ink and would recommend it. I have gone through 2 refills
so far and the ink only stops flowing and only loses intensity when the ink
cartridge runs empty.

I'm having the same negative experience as one of the other reviewers. This ink
seems to dry out, and acts like it ran out of ink even though it is still 75%
full of ink. I love my Jetstream 4+1, and I even like the writing quality of the
ink, but the I can't justify buying more refills when i shouldn't have to.